1) Update on success / market share / etc.
2) Possible update on retail.
3) Compare product that is about to be obsoleted with its competition while putting said competition in an unfavorable light.
4) Make the magic happen and take the press to their happy place.
#3 intrigues me. I can't help but wonder if casting the competition in a negative light is just an excuse for being able to talk about the competition at all. Given the possibility of government interference in any industry it is in the best interest of most businesses to maintain the perception of healthy competition. What has struck me about Apple's portrail of their competitors is that they preset what appears to be a finely tuned mix of recognition, disdain, and paranoia. It's almost as if they want you to remember that there are others out there. Any company that mops the floor with their competition is going to have to deal with the losers running off to the FTC, Congress, etc and whining about anti-competitive practices. At times Apple's presentations seem to be attempting to preempt that sort of thing.
Let me preempt any emotional responses by pointing out that I'm not saying Apple/iOS is better than Google/Andriod, etc, etc. I'm saying that in terms of financial success and overall market/mind share they're doing some serious winning (and not in the Charlie Sheen sense of the word).